Robot and method for manufacturing robot

Abstract

To achieve downsizing of an arm.SOLUTION: A robot 1 includes: a wrist portion 15 and a flange portion 17; a motor 23 housed in the wrist portion 15 and including a first gear 35 that rotates around a motor axis AxM1; a decelerator 25 that decelerates rotation of a second gear 39 and transmits the decelerated rotation to an output shaft 43, the decelerator including the second gear 39 that rotates, in conjunction with rotation of the first gear 35, around a decelerator axis AxR1 parallel to the motor axis AxM1 and offset from the motor axis AxM1, and the output shaft 43 coupled to the flange portion 17; and a brake device 27 that brakes the rotation of the first gear 35, the brake device being housed in the wrist portion 15 so as to face the motor 23 in a direction perpendicular to the motor axis AxM1, and including a third gear 51 that rotates around a brake axis AxB1 parallel to the motor axis AxM1 and the decelerator axis AxR1 and offset from each of the motor axis AxM1 and the decelerator axis AxR1, and rotates in conjunction with the first gear 35 at a position separated from the second gear 39.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The disclosed embodiments relate to a robot and a method for manufacturing a robot.

Background Art

[0002] For example, Patent Document 1 describes a rotary electric machine attached to a robot arm. This rotary electric machine includes a rotary electric machine body that rotates a rotating body about an axis, a braking device that stops the rotation of the rotating body, and a housing that holds the rotary electric machine body and the braking device, and the braking device is disposed at a position offset from the axis of the rotating body.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above prior art, the braking device is provided so as to project axially from the rotary electric machine body at a position offset from the axis of the rotating body. For this reason, there is room for further improvement in terms of miniaturization of the arm.

[0005] The present invention has been made in view of such problems, and an object thereof is to provide a robot and a method for manufacturing a robot that can miniaturize an arm.

Means for Solving the Problems

[0006] To solve the above problems, according to one aspect of the present invention, there is provided a first arm, a second arm rotatably connected to the first arm, a first motor accommodated in the first arm and having a first gear that rotates around a first axis, a second gear that rotates around a second axis parallel to the first axis and offset from the first axis in conjunction with the rotation of the first gear, and a first output shaft connected to the second arm, and a first speed reducer that decelerates the rotation of the second gear and transmits it to the first output shaft. The first arm accommodates a first brake device that rotates around a third axis parallel to the first axis and the second axis and offset from the first axis and the second axis respectively, and that is spaced apart from the second gear and rotates in conjunction with the first gear at a position spaced apart from the second gear, and that brakes the rotation of the first gear. A robot is applied.

[0007] Also, according to another aspect of the present invention, there is provided a method for manufacturing a robot having a first arm and a second arm rotatably connected to the first arm. The method includes a first motor accommodated in the first arm and having a first gear that rotates around a first axis, a second gear that rotates around a second axis parallel to the first axis and offset from the first axis in conjunction with the rotation of the first gear, and a first output shaft connected to the second arm, and a first speed reducer that decelerates the rotation of the second gear and transmits it to the first output shaft. A first brake device having a third gear that rotates around a third axis and brakes the rotation of the first gear is assembled so as to face the first motor in a direction perpendicular to the first axis, the third axis is parallel to the first axis and the second axis and offset from the first axis and the second axis respectively, and the third gear rotates in conjunction with the first gear at a position spaced apart from the second gear. A method for manufacturing a robot is applied.

Effects of the Invention

[0008] According to the robot of the present invention, etc., the arm can be miniaturized.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments will be described with reference to the drawings.

[0011] <1. Configuration of the Robot> With reference to FIG. 1, an example of the configuration of a robot according to an embodiment will be described. FIG. 1 is a perspective view showing an example of the configuration of a robot according to an embodiment.

[0012] As shown in FIG. 1, the robot 1 is configured as a vertically articulated six-axis robot having, for example, six joint portions J1 to J6. An end effector (not shown) corresponding to the work performed by the robot 1 is attached to the tip portion 17a of the robot 1. The end effector is, for example, a robot hand or the like. Note that the robot 1 may be a robot having an axis number other than six (for example, five axes or seven axes). Further, the robot 1 may be a robot other than a vertically articulated robot, such as a horizontally articulated robot or a parallel link robot.

[0013] The robot 1 has a base 3, a turning portion 5, and an arm 7. The base 3 is fixed to, for example, a floor or a pedestal.

[0014] The turning portion 5 is supported by the upper end portion of the base 3 so as to be turnable around a rotation axis Ax1 parallel to the vertical direction. The turning portion 5 is driven to turn around the rotation axis Ax1 with respect to the upper end portion of the base 3 by driving of an actuator Ac1 (not shown) provided in a joint portion J1 that rotatably connects the adjacent base 3 and the turning portion 5.

[0015] The arm 7 is supported by, for example, one side portion of the turning portion 5. The arm 7 has a lower arm portion 9, an elbow portion 11, an upper arm portion 13, a wrist portion 15, and a flange portion 17.

[0016] The lower arm portion 9 is supported by one side portion of the turning portion 5 so as to be turnable around a rotation axis Ax2 perpendicular to the rotation axis Ax1. The lower arm portion 9 is driven to turn around the rotation axis Ax2 with respect to one side portion of the turning portion 5 by driving of an actuator Ac2 (not shown) provided in a joint portion J2 that rotatably connects the adjacent turning portion 5 and the lower arm portion 9.

[0017] The elbow portion 11 is supported by the tip portion of the lower arm portion 9 so as to be turnable around a rotation axis Ax3 parallel to the rotation axis Ax2. The elbow portion 11 is driven to turn around the rotation axis Ax3 with respect to the tip portion of the lower arm portion 9 by driving of an actuator Ac3 (not shown) provided in a joint portion J3 that rotatably connects the adjacent lower arm portion 9 and the elbow portion 11.

[0018] The upper arm 13 is supported at the tip of the elbow 11 so as to be rotatable around a rotation axis Ax4 perpendicular to the rotation axis Ax3. The upper arm 13 is rotationally driven around the rotation axis Ax4 with respect to the tip of the elbow 11 by the drive of an actuator Ac4 (not shown) provided at a joint portion J4 that rotatably connects the adjacent elbow 11 and upper arm 13.

[0019] The wrist 15 is supported at the tip of the upper arm 13 so as to be pivotable around a rotation axis Ax5 perpendicular to the rotation axis Ax4. The wrist 15 is pivotally driven around the rotation axis Ax5 with respect to the tip of the upper arm 13 by the drive of an actuator Ac5 (see FIGS. 3 and 6 described later) provided at a joint portion J5 that rotatably connects the adjacent upper arm 13 and wrist 15.

[0020] The flange portion 17 is supported at the tip of the wrist 15 so as to be rotatable around a rotation axis Ax6 perpendicular to the rotation axis Ax5. The flange portion 17 is rotationally driven around the rotation axis Ax6 with respect to the tip of the wrist 15 by the drive of an actuator Ac6 (see FIGS. 3 and 4 described later) provided at a joint portion J6 that rotatably connects the adjacent wrist 15 and flange portion 17.

[0021] The end effector is attached to the tip 17a of the flange portion 17 and rotates around the rotation axis Ax6 together with the rotation of the flange portion 17 around the rotation axis Ax6.

[0022] The robot 1 having the above configuration is a six-axis robot having six joint portions J1 to J6 provided with six actuators Ac1 to Ac6. Each of the actuators Ac1 to Ac6 that drive the joint portions J1 to J6 is constituted by, for example, a motor, a braking device, a speed reducer, and the like.

[0023] In the above description, the rotation around the rotation axis along the longitudinal direction (or extending direction) of the arm 7 is called "rotation", and the rotation around the rotation axis perpendicular to the longitudinal direction (or extending direction) of the arm 7 is called "pivoting" for distinction.

[0024] Note that the configuration of the robot 1 described above is just an example and is not limited to the above description. For example, a torque sensor may be provided in at least one of the actuators Ac1 to Ac6, or a force sensor may be provided in the robot 1. In this case, when the robot 1 receives an external force, for example, by colliding with a person or an object, it is possible to immediately stop the operation or avoid in the direction opposite to the direction in which the external force acts. Thus, the robot 1 can be configured as a collaborative robot that can operate together with an operator.

[0025] <2.Structure of Actuator Ac6 of Joint Portion J6> Next, with reference to FIGS. 2 to 5, an example of the configuration of the actuator Ac6 provided in the joint portion J6 will be described. FIG. 2 is a perspective view showing an example of a state in which a cover of the wrist portion 15 of the robot 1 is attached, FIG. 3 is a perspective view showing an example of a state in which the cover of the wrist portion 15 of the robot 1 is removed, FIG. 4 is a cross-sectional view showing an example of the configuration of the actuator Ac6 provided in the joint portion J6, and FIG. 5 is a view in the direction of arrow A in FIG. 4, showing an example of the arrangement configuration of each gear of the actuator Ac6.

[0026] As described above, the wrist portion 15 (an example of the first arm) and the flange portion 17 (an example of the second arm) are rotatably connected around the rotation axis Ax6 by the joint portion J6. As shown in FIGS. 2 and 3, the wrist portion 15 has a bent portion 15a bent in an L shape. An opening 19 and a cover 21 for closing the opening 19 are provided on the outer side of the bent portion 15a that is convex. The cover 21 is fixed to the opening 19 by, for example, a plurality of bolts (not shown). As shown in FIG. 3, in a state where the cover 21 is removed, the actuator Ac6 provided in the joint portion J6 is exposed. The actuator Ac6 has a motor 23 and a brake device 27.

[0027] FIG. 4 shows an example of the configuration of the actuator Ac6. As shown in FIG. 4, the actuator Ac6 has a motor 23, a speed reducer 25, a brake device 27, and an intermediate gear device 29.

[0028] The motor 23 (an example of the first motor) is housed in the wrist part 15. The motor 23 has a motor housing 31 that houses a rotor, a stator, etc., and a first gear 35 that is connected to a motor shaft 33 protruding from the motor housing 31 and rotates around a motor axis AxM1 (an example of the first axis). The motor housing 31 is fixed to the housing 15a of the wrist part 15. The dimension L1 of the motor 23 in the direction of the motor axis AxM1 is longer than the dimension L2 of the brake device 27 in the direction of the brake axis AxB1.

[0029] The speed reducer 25 (an example of the first speed reducer) has a second gear 39 connected to an input shaft 37, a fixing part 41, and an output shaft 43 (an example of the first output shaft), and decelerates the rotation of the second gear 39 and transmits it to the output shaft 43. The input shaft 37 is rotatably supported by a bearing 45 with respect to the housing 15a of the wrist part 15, and the second gear 39 rotates around a speed reducer axis AxR1 (an example of the second axis) in conjunction with the rotation of the first gear 35 of the motor 23. The speed reducer axis AxR1 is parallel to the motor axis AxM1 and is offset from the motor axis AxM1 by a predetermined distance. The bearing 45 is attached to the housing 15a in a state where an appropriate pressing force is applied so as to support both the radial force and the thrust force acting on the input shaft 37 and the second gear 39. The fixing part 41 is fixed to the housing 15a of the wrist part 15. The output shaft 43 is fixed to the housing 17b of the flange part 17 and rotates around the speed reducer axis AxR1 with respect to the fixing part 41. The speed reducer axis AxR1 substantially coincides with the aforementioned rotation axis Ax6.

[0030] The speed reducer 25 has a hollow part 46 (an example of the first hollow part) that extends along the speed reducer axis AxR1 in the second gear 39, the input shaft 37, the fixing part 41, and the output shaft 43.

[0031] The brake device 27 (an example of the first brake device) is housed in the wrist part 15 such that at least a part thereof faces the motor 23 in a direction perpendicular to the motor axis AxM1 (the vertical direction in FIG. 4). In the example shown in FIG. 4, the entire axial direction of the brake device 27 is arranged to face the motor 23. Here, the term "opposite" means that the region in the direction of the motor axis AxM1 where the motor 23 is arranged and the region in the direction of the brake axis AxB1 where the brake device 27 is arranged overlap when viewed from a direction perpendicular to the motor axis AxM1 (brake axis AxB1). The brake device 27 includes a brake housing 47 that houses an electromagnetic part and the like, and a third gear 51 that is connected to a brake shaft 49 protruding from the brake housing 47 and rotates around the brake axis AxB1 (an example of the third axis). The brake axis AxB1 is parallel to the motor axis AxM1 and the reduction gear axis AxR1, and is offset from the motor axis AxM1 and the reduction gear axis AxR1 by a predetermined distance, respectively. The third gear 51 rotates in conjunction with the first gear 35 of the motor 23. Thereby, the brake device 27 brakes the rotation of the first gear 35 of the motor 23. The brake housing 47 is fixed to the housing 15a of the wrist part 15.

[0032] The intermediate gear device 29 is housed in the wrist part 15. The intermediate gear device 29 includes a gear housing 53 that houses bearings and the like, and a fourth gear 57 that is connected to a gear shaft 55 protruding from the gear housing 53 and rotates around the gear axis AxG1 (an example of the fourth axis). The gear axis AxG1 is parallel to the motor axis AxM1, the reduction gear axis AxR1, and the brake axis AxB1, and is offset from the motor axis AxM1, the reduction gear axis AxR1, and the brake axis AxB1 by a predetermined distance, respectively. The fourth gear 57 is arranged between the third gear 51 of the brake device 27 and the first gear 35 of the motor 23, and transmits the braking force of the third gear 51 to the first gear 35. The fourth gear 57 is a so-called idler gear. The gear housing 53 is fixed to the housing 15a of the wrist part 15.

[0033] Fig. 5 shows an example of the arrangement of each gear of the actuator Ac6 when viewed from the direction of arrow A in Fig. 4. As shown in Fig. 5, the first gear 35 of the motor 23 and the second gear 39 of the speed reducer 25 are directly connected by meshing with each other. Further, the third gear 51 of the brake device 27 rotates in conjunction with the first gear 35 at a position separated from the second gear 39. Specifically, the third gear 51 and the fourth gear 57 mesh with each other, and the fourth gear 57 and the first gear 35 mesh with each other, so that the third gear 51 and the first gear 35 are connected at a position separated from the second gear 39. The third gear 51 is provided so as to have a gap with the second gear 39, and the fourth gear 57 is provided so as to have a gap with the second gear 39. With the above gear configuration, the brake device 27 brakes the rotation of the first gear 35 of the motor 23 via the fourth gear 57. The number of teeth of the third gear 51 is equal to or greater than that of the first gear 35 so that the motor axis AxM1 of the motor 23 and the brake axis AxB1 of the brake device 27 are directly connected and arranged concentrically.

[0034] Note that the first gear 35 and the second gear 39 do not have to be directly connected as long as they are configured to rotate in conjunction with each other. For example, a configuration in which some power transmission mechanism such as another gear is interposed between them may be used. Further, the third gear 51 and the first gear 35 may be configured to directly mesh with each other without passing through the fourth gear 57. Further, a plurality of fourth gears 57 may be interposed between the third gear 51 and the first gear 35. Further, the number of teeth of the third gear 51 may be made larger than the number of teeth of the first gear 35 as necessary.

[0035] <3. Configuration of Actuator Ac5 of Joint Portion J5> Next, with reference to Figs. 3, 6, and 7, an example of the configuration of the actuator Ac5 provided in the joint portion J5 will be described. Fig. 6 is a cross-sectional view showing an example of the configuration of the actuator Ac5 provided in the joint portion J5, and Fig. 7 is a view in the direction of arrow B in Fig. 6 showing an example of the arrangement of each gear of the actuator Ac5.

[0036] As described above, the upper arm portion 13 (an example of the third arm) and the wrist portion 15 are rotatably connected around the rotation axis Ax5 by the joint portion J5. As shown in FIG. 3, when the cover 21 of the wrist portion 15 is removed, the actuator Ac5 provided in the joint portion J5 is exposed together with the actuator Ac6. The actuator Ac5 has a motor 59 and a brake device 63. The motor 23 and the brake device 27 of the actuator Ac6 and the motor 59 and the brake device 63 of the actuator Ac5 are arranged so as not to interfere with each other and are housed in the wrist portion 15.

[0037] FIG. 6 shows an example of the configuration of the actuator Ac5. As shown in FIG. 6, the actuator Ac5 has a motor 59, a speed reducer 61, a brake device 63, and an intermediate gear device 65.

[0038] The motor 59 (an example of the second motor) is housed in the wrist portion 15. The motor 59 has a motor housing 67 that houses a rotor, a stator, etc., and a fifth gear 71 that is connected to a motor shaft 69 protruding from the motor housing 67 and rotates around a motor axis AxM2 (an example of the fifth axis). The motor housing 67 is fixed to the housing 15a of the wrist portion 15. The dimension L3 of the motor 59 in the direction of the motor axis AxM2 is longer than the dimension L4 of the brake device 63 in the direction of the brake axis AxB2.

[0039] The speed reducer 61 (an example of the second speed reducer) has a sixth gear 75 connected to the input shaft 73, a fixed portion 77, and an output shaft 79 (an example of the second output shaft), and decelerates the rotation of the sixth gear 75 and transmits it to the output shaft 79. The input shaft 73 is rotatably supported by a bearing 81 with respect to the housing 15a of the wrist portion 15, and the sixth gear 75 rotates around the speed reducer axis AxR2 (an example of the sixth axis) in conjunction with the rotation of the fifth gear 71 of the motor 59. The speed reducer axis AxR2 is parallel to the motor axis AxM2 and is offset from the motor axis AxM2 by a predetermined distance. The bearing 81 is attached to the housing 15a in a state where appropriate pressing force is applied so as to support both the radial force and the thrust force acting on the input shaft 73 and the sixth gear 75. The fixed portion 77 is fixed to the housing 15a of the wrist portion 15. The output shaft 79 is fixed to the housing 13a of the upper arm portion 13 and rotates around the speed reducer axis AxR2 with respect to the fixed portion 77. The speed reducer axis AxR2 substantially coincides with the aforementioned rotation axis Ax5.

[0040] The speed reducer 61 has a hollow portion 83 (an example of the second hollow portion) extending along the speed reducer axis AxR2 in the sixth gear 75, the input shaft 73, the fixed portion 77, and the output shaft 79.

[0041] The brake device 63 (an example of the second brake device) is housed in the wrist part 15 such that at least a part thereof faces the motor 59 in a direction perpendicular to the motor axis AxM2 (the vertical direction in FIG. 6). In the example shown in FIG. 6, the entire axial direction of the brake device 63 is arranged to face the motor 59. Here, the term "opposite" means that the region in the direction of the motor axis AxM2 where the motor 59 is arranged and the region in the direction of the brake axis AxB2 where the brake device 63 is arranged overlap when viewed from a direction perpendicular to the motor axis AxM2 (brake axis AxB2). The brake device 63 includes a brake housing 85 that houses an electromagnetic part and the like, and a seventh gear 89 that is connected to a brake shaft 87 protruding from the brake housing 85 and rotates around the brake axis AxB2 (an example of the seventh axis). The brake axis AxB2 is parallel to the motor axis AxM2 and the reduction gear axis AxR2, and is offset from the motor axis AxM2 and the reduction gear axis AxR2 by a predetermined distance, respectively. The seventh gear 89 rotates in conjunction with the fifth gear 71 of the motor 59. Thereby, the brake device 63 brakes the rotation of the fifth gear 71 of the motor 59. The brake housing 85 is fixed to the housing 15a of the wrist part 15.

[0042] The intermediate gear device 65 is housed in the wrist part 15. The intermediate gear device 65 includes a gear housing 91 that houses bearings and the like, and an eighth gear 95 that is connected to a gear shaft 93 protruding from the gear housing 91 and rotates around the gear axis AxG2. The gear axis AxG2 is parallel to the motor axis AxM2, the reduction gear axis AxR2, and the brake axis AxB2, and is offset from the motor axis AxM2, the reduction gear axis AxR2, and the brake axis AxB2 by a predetermined distance, respectively. The eighth gear 95 is arranged between the seventh gear 89 of the brake device 63 and the fifth gear 71 of the motor 59, and transmits the braking force of the seventh gear 89 to the fifth gear 71. The eighth gear 95 is a so-called idler gear. The gear housing 91 is fixed to the housing 15a of the wrist part 15.

[0043] FIG. 7 shows an example of the arrangement of each gear of the actuator Ac5 when viewed from the direction of arrow B in FIG. 6. As shown in FIG. 7, the fifth gear 71 of the motor 59 and the sixth gear 75 of the speed reducer 61 are directly connected by meshing with each other. Further, the seventh gear 89 of the brake device 63 rotates in conjunction with the fifth gear 71 at a position separated from the sixth gear 75. Specifically, the seventh gear 89 and the eighth gear 95 mesh with each other, and the eighth gear 95 and the fifth gear 71 mesh with each other, so that the seventh gear 89 and the fifth gear 71 are connected at a position separated from the sixth gear 75. The seventh gear 89 is provided so as to have a gap with the sixth gear 75, and the eighth gear 95 is provided so as to have a gap with the sixth gear 75. With the above gear configuration, the brake device 63 brakes the rotation of the fifth gear 71 of the motor 59 via the eighth gear 95. The number of teeth of the seventh gear 89 is equal to or more than that in the case where the motor axis AxM2 of the motor 59 and the brake axis AxB2 of the brake device 63 are directly connected in a concentric arrangement, and is equal to or less than the number of teeth of the fifth gear 71.

[0044] Note that the fifth gear 71 and the sixth gear 75 do not necessarily have to be directly connected as long as they are configured to rotate in conjunction with each other. For example, a configuration in which some power transmission mechanism such as another gear is interposed between them may be used. Further, the seventh gear 89 and the fifth gear 71 may be configured to mesh directly without passing through the eighth gear 95. Also, a configuration in which a plurality of eighth gears 95 are interposed between the seventh gear 89 and the fifth gear 71 may be used. Further, if necessary, the number of teeth of the seventh gear 89 may be made larger than the number of teeth of the fifth gear 71.

[0045] <4. Arrangement of Motors and Brake Devices of Actuators Ac5 and Ac6> Next, with reference to FIGS. 3 and 8 to 10, an example of the arrangement of the motors 23, 59 of the actuators Ac5, Ac6 and the braking devices 27, 63 housed in the wrist part 15 will be described. FIG. 8 is a schematic view schematically showing an example of the arrangement of the motors 23, 59 and the braking devices 27, 63 when viewed from the direction of arrow C in FIG. 3, FIG. 9 is a schematic view schematically showing an example of the arrangement of the motors 23, 59 and the braking devices 27, 63 when viewed from the direction of arrow D in FIG. 3, and FIG. 10 is a schematic view schematically showing an example of the arrangement of the motors 23, 59 and the braking devices 27, 63 when viewed from the direction of arrow E in FIG. 3.

[0046] As shown in FIG. 3 described above, the motor 23 and the braking device 27 constituting the actuator Ac6, and the motor 59 and the braking device 63 constituting the actuator Ac5 are housed in the wrist part 15 in an alternating arrangement so as not to interfere with each other.

[0047] Specifically, as shown in FIGS. 8 to 10, the motor housing 31 of the motor 23 and the brake housing 47 of the braking device 27 are provided so as to project along the direction of the reduction gear shaft center AxR1 (rotating shaft Ax6) from the reduction gear 25. Further, the motor housing 67 of the motor 59 and the brake housing 85 of the braking device 63 are provided so as to project along the direction of the reduction gear shaft center AxR2 (rotating shaft Ax5) from the reduction gear 61.

[0048] As shown in FIG. 8, the motor housing 31 (an example of the first housing) of the motor 23 is disposed on the radially outer side of a substantially cylindrical wiring space S1 (an example of the first space) obtained by extending the hollow portion 46 of the reduction gear 25 in the direction of the reduction gear shaft center AxR1. Similarly, the brake housing 47 (an example of the second housing) of the braking device 27 is also disposed on the radially outer side of the wiring space S1.

[0049] As shown in FIG. 10, the motor housing 67 (an example of the third housing) of the motor 59 is disposed radially outside a substantially cylindrical wiring space S2 (an example of the second space) obtained by extending the hollow portion 83 of the speed reducer 61 in the direction of the speed reducer axis AxR2. Similarly, the brake housing 85 (an example of the fourth housing) of the brake device 63 is also disposed radially outside the wiring space S2.

[0050] As shown in FIG. 9, a bent wiring space S3 (an example of the third space) is formed by connecting the wiring space S1 and the wiring space S2. Cables and the like inserted through the hollow portions 46 and 83 are wired through the wiring space S3 inside the wrist portion 15. As shown in FIGS. 8 to 10, the motor housing 31 of the motor 23, the brake housing 47 of the brake device 27, the motor housing 67 of the motor 59, and the brake housing 85 of the brake device 63 are arranged so that the housings do not interfere with each other and do not interfere with the wiring space S3.

[0051] As shown in FIGS. 8 and 10, the speed reducer axis AxR1 (rotation axis Ax6) of the speed reducer 25 and the speed reducer axis AxR2 (rotation axis Ax5) of the speed reducer 61 intersect at a predetermined angle on the same plane P including both of the speed reducer axes AxR1 and AxR2. The predetermined angle is, for example, approximately 90 degrees, but may intersect at an angle other than 90 degrees. The motor axis AxM1 of the motor 23 is disposed on one side of the plane P (the upper side in FIGS. 8 and 10), and the motor axis AxM2 of the motor 59 is disposed on the other side of the plane P (the lower side in FIGS. 8 and 10).

[0052] In addition, in order to arrange the brake device 27 so as not to interfere with the two motors 23 and 59, the other brake device 63, and the wiring space S3, a fourth gear 57 for adjusting the relative position between the motor 23 and the brake device 27 may be provided. Similarly, in order to arrange the brake device 63 so as not to interfere with the two motors 23 and 59, the other brake device 27, and the wiring space S3, an eighth gear 95 for adjusting the relative position between the motor 59 and the brake device 63 may be provided.

[0053] The manufacturing method of the robot 1 having the configuration described above includes a step of assembling a brake device 27, which is provided with a third gear 51 that rotates around a brake axis AxB1 and brakes the rotation of the first gear 35, in a position where the brake axis AxB1 is parallel to the motor axis AxM1 and the reduction gear axis AxR1 and separated from the motor axis AxM1 and the reduction gear axis AxR1, respectively, and the third gear 51 rotates in conjunction with the first gear 35 at a position separated from the second gear 39, so as to face the motor 23 in a direction perpendicular to the motor axis AxM1. The motor 23 is housed in the wrist portion 15 and includes a first gear 35 that rotates around the motor axis AxM1, a second gear 39 that rotates around a reduction gear axis AxR1 that is parallel to the motor axis AxM1 and displaced from the motor axis AxM1 in conjunction with the rotation of the first gear 35, and a reduction gear 25 that is connected to the flange portion 17 and transmits the decelerated rotation of the second gear 39 to the output shaft 43.

[0054] <5. Effects of the Embodiment> As described above, in the robot 1 of the present embodiment, the motor 23 housed in the wrist portion 15 rotates the first gear 35 around the motor axis AxM1, so that the second gear 39 of the reduction gear 25 rotates in conjunction with the rotation, and the rotation of the second gear 39 is decelerated and transmitted to the output shaft 43 connected to the flange portion 17, whereby the flange portion 17 rotates with respect to the wrist portion 15. Further, the third gear 51 that rotates in conjunction with the first gear 35 at a position separated from the second gear 39 of the brake device 27 rotates around the brake axis AxB1 that is parallel to and displaced from the motor axis AxM1, so that the rotation of the first gear 35 is braked. According to the present embodiment, the motor 23 and the brake device 27 are arranged offset in a direction perpendicular to the motor axis AxM1 (brake axis AxB1) and face each other in the direction. Thereby, the axial dimension of the actuator Ac6 including the motor 23, the reduction gear 25, and the brake device 27 can be reduced. Therefore, the wrist portion 15 that houses the actuator Ac6 can be reduced in size. Note that the actuator Ac5 can obtain the same effects as described above with the same configuration.

[0055] Also, in the present embodiment, instead of connecting the third gear 51 of the brake device 27 to the second gear 39 of the speed reducer 25, the first gear 35 of the motor 23 may be connected. That is, the third gear 51 of the brake device 27 may be connected to the first gear 35 of the motor 23 without passing through the second gear 39 of the speed reducer 25. In this case, due to play in the gears and the like, disturbance factors that the behavior of the third gear 51 of the brake device 27 imparts to the second gear 39 of the speed reducer 25 can be reduced. Also, since the number of gears connected to the second gear 39 of the speed reducer 25 can be reduced, wear of the second gear 39 can be reduced. Note that the actuator Ac5 can also achieve the same effects as described above with the same configuration as above.

[0056] In the above case, since the second gear 39 of the speed reducer 25 and the third gear 51 (the fourth gear 57 in the above embodiment) of the brake device 27 are connected to the first gear 35 of the motor 23, wear of the first gear 35 may increase. However, since the motor 23 is exposed by removing the cover 21 and is easy to remove, the first gear 35 is easy to replace. On the other hand, the speed reducer 25 cannot be removed unless the motor 23, the brake device 27, etc. are removed after removing the cover 21, so it takes time to replace the second gear 39 of the speed reducer 25. Therefore, the configuration of the present embodiment has the advantage that maintenance is easier compared to, for example, the case where both the first gear 35 of the motor 23 and the third gear 51 of the brake device 27 are connected to the second gear 39 of the speed reducer 25. Note that the actuator Ac5 can also achieve the same effects as described above with the same configuration as above.

[0057] Also, in the present embodiment, the dimension L1 of the motor 23 in the direction of the motor axis AxM1 may be made longer than the dimension L2 of the brake device 27 in the direction of the brake axis AxB1. In this case, since the dimension of the brake device 27 in the direction of the motor axis AxM1 (brake axis AxB1) can be accommodated within the dimension of the motor 23, the axial dimension of the actuator Ac6 can be further reduced. Note that the actuator Ac5 can also achieve the same effects as described above with the same configuration as above.

[0058] In this embodiment, the reducer 25 may have a hollow portion 46 extending along the reducer axis AxR1 in the second gear 39 and the output shaft 43, the motor 23 may have a motor housing 31 arranged radially outside the wiring space S1 in which the hollow portion 46 is extended in the direction of the reducer axis AxR1, and the brake device 27 may have a brake housing 47 arranged radially outside the wiring space S1. In this case, since the reducer 25 has the hollow portion 46, cables and the like can be wired through the reducer 25. In addition, since the motor housing 31 of the motor 23 and the brake housing 47 of the brake device 27 are arranged radially outside the wiring space S1 in which the hollow portion 46 is extended, it is possible to prevent the cables and the like drawn out from the hollow portion 46 from interfering with the motor housing 31 and the brake housing 47. Therefore, a space for passing the cables and the like drawn out from the hollow portion 46 can be secured in the wrist portion 15. The actuator Ac5 can also obtain the same effect as above by a similar configuration as above.

[0059] In this embodiment, a fourth gear 57 may be provided to transmit the braking force of the third gear 51 to the first gear 35. In this case, the fourth gear 57 is interposed between the first gear 35 of the motor 23 and the third gear 51 of the brake device 27, so that the distance between the motor axis AxM1 and the brake axis AxB1 can be adjusted. Therefore, it is possible to arrange the motor 23 and the brake device 27 so that the motor housing 31 and the brake housing 47 do not interfere with each other while suppressing the sizes of the first gear 35 and the third gear 51, or to arrange the motor housing 31 and the brake housing 47 so that they do not interfere with the wiring space S1 that is an extension of the hollow portion 46, and the degree of freedom in arranging the motor 23 and the brake device 27 can be improved. The actuator Ac5 can also be configured in a similar manner to the above to obtain the same effect as above.

[0060] Further, in the present embodiment, the number of teeth of the third gear 51 may be equal to or less than the number of teeth of the first gear 35. In this case, the braking torque by the braking device 27 can be increased. Thereby, for example, when a braking unit similar to the braking device 27 is provided on the anti-load side of the motor 23, it is possible to apply a braking torque equal to or greater than that in the case of a motor with a brake. Note that the actuator Ac5 can also obtain the same effect as described above with the same configuration as above.

[0061] Further, in the present embodiment, the motor 23 and the braking device 27 that relatively drive or stop the wrist part 15 and the flange part 17, and the motor 59 and the braking device 63 that relatively drive or stop the wrist part 15 and the upper arm part 13 may be housed in the wrist part 15 in an alternating arrangement so as not to interfere with each other. In this case, the space inside the wrist part 15 can be effectively utilized to compactly house each device. Also, each of the motor 23, the braking device 27, the motor 59, and the braking device 63 may be arranged so as not to interfere with a bent wiring space S3 that connects the wiring space S1 and the wiring space S2. In this case, a space for passing a cable or the like routed between the hollow part 46 and the hollow part 83 can be secured inside the wrist part 15.

[0062] Further, in the present embodiment, the motor axis AxM1 of the motor 23 may be arranged on one side of a plane P including the reduction gear axes AxR1 and AxR2 that intersect each other, and the motor axis AxM2 of the motor 59 may be arranged on the other side of the plane P. In this case, while preventing the motor 23 and the motor 59 from interfering with each other, the accommodation spaces of the motor 23 and the motor 59 can be made more compact.

[0063] <6. Modification Example> The disclosed embodiment is not limited to the above, and various modifications are possible without departing from the spirit and technical idea thereof.

[0064] In the above description, the configuration of the above embodiment was applied to the actuator Ac6 provided at the joint J6 that rotatably connects the wrist part 15 and the flange part 17 among the arms 7 of the robot 1, or to the actuator Ac5 provided at the joint J5 that rotatably connects the wrist part 15 and the upper arm part 13. However, the applicable location is not limited to the actuators Ac5 and Ac6. The configuration of the above embodiment may be applied to other locations of the arm 7, such as the actuator Ac4 of the joint J4 that rotatably connects the elbow part 11 and the upper arm part 13, or the actuator Ac3 of the joint J3 that rotatably connects the elbow part 11 and the lower arm part 9.

[0065] Also, in the above description, the case where the configuration of the above embodiment is applied to both of the actuators Ac5 and Ac6 has been described. However, it may be applied to only one of the actuators Ac5 and Ac6.

[0066] In the above description, when there are descriptions such as "vertical", "parallel", "plane", etc., such descriptions do not have a strict meaning. Those "vertical", "parallel", "plane" mean "substantially vertical", "substantially parallel", "substantially plane" in that tolerances and errors in design and manufacturing are allowed.

[0067] In the above description, when there are descriptions such as "identical", "the same", "equal", "different", etc. regarding the dimensions, sizes, shapes, positions, etc. in appearance, such descriptions do not have a strict meaning. Those "identical", "the same", "equal", "different" mean "substantially identical", "substantially the same", "substantially equal", "substantially different" in that tolerances and errors in design and manufacturing are allowed.

[0068] In addition to what has been already described above, the methods according to the above embodiment and each modification example may be appropriately combined and used. In addition, although not exemplified one by one, the above embodiment and each modification example may be implemented with various changes made within the scope not departing from the gist thereof.

[0069] The problems and effects to be solved by the above-described embodiments, modifications, etc. are not limited to the above-described content. Depending on the embodiments, modifications, etc., it is possible to solve problems not described above or to achieve effects not described above, or to solve only some of the described problems or to achieve only some of the described effects.

Explanation of Signs

[0070] 1 Robot 13 Upper Arm (an example of the third arm) 15 Wrist (an example of the first arm) 17 Flange (an example of the second arm) 23 Motor (an example of the second arm) 25 Reducer (an example of the first reducer) 27 Brake Device (an example of the first brake device) 29 Intermediate Gear Device 31 Motor Housing (an example of the first housing) 35 First Gear 39 Second Gear 43 Output Shaft (an example of the first output shaft) 46 Hollow Portion 47 Brake Housing (an example of the second housing) 51 Third Gear 57 Fourth Gear 59 Motor (an example of the second motor) 61 Reducer (an example of the second reducer) 63 Brake Device (an example of the second brake device) 65 Intermediate Gear Device 67 Motor Housing (an example of the third housing) 71 Fifth Gear 75 Sixth Gear 79 Output Shaft (an example of the second output shaft) 83 Hollow Portion (an example of the second hollow portion) 85 Brake Housing (an example of the fourth housing) 89 Seventh Gear 95 Eighth Gear AxB1 Brake Axis (an example of the third axis) AxB2 Brake Axis (an example of the seventh axis) AxG1 Gear axis center (an example of the fourth axis center) AxG2 Gear axis center AxM1 Motor axis center (an example of the first axis center) AxM2 Motor axis center (an example of the fifth axis center) AxR1 Reducer axis center (an example of the second axis center) AxR2 Reducer axis center (an example of the sixth axis center) L1 Dimension L2 Dimension L3 Dimension L4 Dimension P Plane S1 Wiring space (an example of the first space) S2 Wiring space (an example of the second space) S3 Wiring space (an example of the third space)

Claims

1. a first arm, a second arm rotatably connected to the first arm, a first motor housed in the first arm and having a first gear that rotates around a first axis, a second gear that rotates around a second axis parallel to and offset from the first axis in conjunction with the rotation of the first gear, and a first output shaft connected to the second arm, the first reduction gear that reduces the rotation of the second gear and transmits it to the first output shaft, a first braking device that is housed in the first arm so as to face the first motor in a direction perpendicular to the first axis, rotates around a third axis parallel to the first axis and the second axis and offset from the first axis and the second axis respectively, and has a third gear that rotates in conjunction with the first gear at a position spaced apart from the second gear, and brakes the rotation of the first gear, a robot having the above.

2. The first gear is, connected to the second gear, The third gear is, provided so as to have a gap with the second gear, The robot according to claim 1.

3. The dimension of the first motor in the direction of the first axis is, longer than the dimension of the first braking device in the direction of the third axis, The robot according to claim 1 or 2.

4. The first reduction gear has, a first hollow portion extending along the second axis in the second gear and the first output shaft, The first motor has, a first housing disposed radially outside the diameter of a first space extending the first hollow portion in the direction of the second axis, The first braking device has, a second housing disposed radially outside the first space, The robot according to claim 1 or 2.

5. at least one fourth gear that is housed in the first arm, rotates around a fourth axis parallel to the first axis, the second axis, and the third axis and offset from the first axis, the second axis, and the third axis respectively, and transmits the braking force of the third gear to the first gear, The robot according to claim 4.

6. The number of teeth of the third gear is, less than or equal to the number of teeth of the first gear, The robot according to claim 1 or 2.

7. a third arm rotatably connected to a position of the first arm different from the second arm, a second motor housed in the first arm and having a fifth gear that rotates around a fifth axis, A sixth gear that rotates around a sixth axis that is parallel to the fifth axis and offset from the fifth axis and intersects the second axis in conjunction with the rotation of the fifth gear, and a second output shaft connected to the third arm, and a second speed reducer that decelerates the rotation of the sixth gear and transmits it to the second output shaft. A second brake device that is housed in the first arm so as to face the second motor in a direction perpendicular to the fifth axis, rotates around a seventh axis that is parallel to the fifth axis and the sixth axis and offset from the fifth axis and the sixth axis respectively, and rotates in conjunction with the fifth gear at a position separated from the sixth gear, and brakes the rotation of the fifth gear. Further comprising The second speed reducer Has a second hollow portion extending along the sixth axis in the sixth gear and the second output shaft. The second motor Has a third housing disposed on the radially outer side of a second space obtained by extending the second hollow portion in the direction of the sixth axis. The second brake device Has a fourth housing disposed on the radially outer side of the second space. Each of the first motor, the first brake device, the second motor, and the second brake device is arranged so as not to interfere with a third space having a bent shape connecting the first space and the second space. The robot according to claim 4.

8. The first axis of the first motor Is disposed on one side of a plane including the second axis and the sixth axis that intersect each other. The fifth axis of the second motor Is disposed on the other side of the plane. The robot according to claim 7.

9. A first arm, A second arm rotatably connected to the first arm, A method for manufacturing a robot having A first motor provided with a first gear that is housed in the first arm and rotates around a first axis, a second gear that rotates around a second axis that is parallel to the first axis and offset from the first axis in conjunction with the rotation of the first gear, and a first output shaft connected to the second arm, and with respect to a first speed reducer that decelerates the rotation of the second gear and transmits it to the first output shaft. Provided is a first brake device that includes a third gear that rotates around a third axis and brakes the rotation of the first gear. The first brake device faces the first motor in a direction perpendicular to the first axis, the third axis is parallel to the first axis and the second axis and is spaced apart from the first axis and the second axis respectively, and the third gear is spaced apart from the second gear and is assembled so as to rotate in conjunction with the first gear at a position where the third gear is spaced apart from the second gear. A method for manufacturing a robot having the above.

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